Is there a way to avoid my structure running into itself?

Hi!
I'm designing a custom structure and so far everything is going really well, thanks to your guys' earlier help.
My dungeon has a modular design where all building blocks are 9x6x9 blocks or a multiple of that. Sometimes, a corridor curves back onto itself and tries to generate into the wall of a structure generated earlier (see screenshot made in spectator mode). I realise this is what fallback structures are for; however, since there is exactly 0 space between the two existing structures, the fallback option cannot spawn.
I'm wondering if there is any way to avoid this from happening or to 'go back' one step in generation when this happens. I'm not too fussed if this issue has no fix, since it is not too ugly and doesn't seem to happen too often. Still, a fix would be nice 🙂
Curious to hear your thoughts